The Olympic Games seem to celebrate the extremes of athletic physique — from tiny gymnasts to impossibly huge shot-putters. But why are they shaped that way?

We've put together an infographic that explores how athletes' bodies have changed over the last century, and the role physics plays in each event. Here on Shots, we're taking a look at some of the athletes featured in the graphic.

Men's 100-Meter Sprint

For decades, sprinters have been getting taller, propelled upward by a simple law of physics. Sprinting is basically a controlled forward fall. Runners with higher centers of gravity can fall forward faster — and the taller you are, the higher your center of gravity.

Athletes of West African descent have a center of gravity that is 3 percent higher than Europeans, and they tend to dominate sprinting events.

Women's Marathon

The biggest problem for marathon runners is body heat. Having a small, thin body helps maximize heat dissipation. While some distance runners are shorter and some are taller, all are extremely light.

Men's Weightlifting

Weightlifters come in all sizes, but they tend to have one thing in common: short legs and short arms. Because of their shorter limbs, they don't have to lift their barbells quite so high, so they expend less energy.

Bantamweight champions can lift three times their body weight — heavyweights, less than two.

Women's Single Scull

Rowing favors tall athletes who can take long, powerful strokes for efficient sculling.

Men's Gymnastics

If you are going to be twisting and turning rapidly through the air, it helps if there is less of you to turn. That's one reason gymnasts are so small. They have some of the lowest body fat percentages in sports, and the body mass index of gold medalists has been declining for the past 50 years.

There are a lot more details about the physics behind Olympic physiques in the full infographic, so be sure to check it out.

Copyright 2013 NPR. To see more, visit http://www.npr.org/.

Transcript

STEVE INSKEEP, HOST:

If you've been following the Olympics at all over the past couple of weeks, you've probably noticed some extreme body shapes - from tiny gymnasts to enormous basketball stars. Those athletes are shaped by years of intense training, and also by the laws of physics. Here's NPR's Adam Cole.

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ADAM COLE, BYLINE: Back in 1929, the fastest man in the world was Eddie Tolan.

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COLE: Tolan was a Detroit native who chewed gum while he raced, and taped his horn-rimmed glasses to his head. He was a stocky 5-and-a-half-feet tall, and ran the 100-meter dash in 10.4 seconds.

COLE: He's 6-foot-5. For decades, sprinters have been getting taller, propelled upward by a simple law of physics. Sprinting is, basically, a controlled, forward fall. Athletes with higher centers of gravity can fall forward faster. And the taller you are, the higher your center of gravity.According to some physicists, this is one reason that Bolt breezes past his shorter competitors.

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COLE: Swimmers are getting taller, too, but they're an entirely different kettle of fish. Picture Michael Phelps - impossibly long arms; short, powerful legs; and huge feet - that all help propel him through the water. Then there's the long, tapered torso. It's a shape seals and shipbuilders have perfected. And it means less drag, and a swifter flight through the water.

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COLE: Now let's go to the other end of the size spectrum, to gymnastics. Here, the physics of rotation reigns.

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COLE: Making sudden turns in the air requires a lot of strength.

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COLE: The less of you there is to turn, the better. So you want most of your weight to be muscle. It's no surprise gymnasts are small, and they have some of the lowest percentages of body fat in sports. Since the '60s, the body mass index of gold medalists has been getting smaller, not bigger.

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UNIDENTIFIED ANNOUNCER #2: No man has ever lifted 500 pounds in competition - a quarter of a ton. Look at the concentration on that face.

COLE: But thanks to physics, they all have something in common: short legs and short arms. If you have shorter limbs, you don't have to lift your barbells quite so high.

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COLE: You can size up past record holders and today's Olympians - in all these events and more - at our website, npr.org.

Adam Cole, NPR News.

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INSKEEP: If you're strong enough to lift a device, or a mouse, you can go to npr.org and read our Summer Olympics blog, "The Torch." You can read about the run made by the first female track and field athlete to represent Saudi Arabia. You can continue following this program throughout the day on social media. We're on Facebook. You can also find many of us on Twitter, among other places. We are @MORNING EDITION and @NPRinskeep.